Genetic engineering, widely decried by enviromentalists as interfering
with good old Mother Nature, may ultimately provide critical
componants of the mess we're in as a species and as a planet. Just as
some folks are working to engineer a bug (bacteria, i.e.) that can
produce molecular hydrogen in commercial quantities, while others are
training germs (bacteria - we sure have a lot of slang words for these
guys don't we??) to turn cellulose into fuel in an energy-efficient
manner, other bio-engineering companies are coaxing bacteria to
produce biofuels that WON'T harm the biosphere - well certainly not as
much as planting hundreds of km2 of sugar cane or palm trees on top of
precious mature ecosystems.....one HAS to ask, however: Why aren't
governments around the world funding this kind of research??? Are
they too much in the pockets of Big Oil, Agribusiness giants and other
corporate interests that stand to lose market share if biotech firms
come up with better solutions than they do? Or are there other reasons
also?
Ross Mayhew - Climate Concern
http://www.enn.com/pollution/article/37480
The biofuels of the future will be tailor-made
BURIED in the news a few weeks ago was an announcement by a small
Californian firm called Amyris. It was, perhaps, a parable for the
future of biotechnology. Amyris is famous in the world of tropical
medicine for applying the latest biotechnological tools to the
manufacture of artemisinin, an antimalarial drug that is normally
extracted from a Chinese vine. The vines cannot produce enough of the
stuff, though, so Amyris?s researchers have taken a few genes here and
there, tweaked them and stitched them together into a biochemical
pathway enabling bacteria to make a chemical precursor that can easily
be converted into the drug.
But that is not what the announcement was about. Instead, it was that
Amyris was going into partnership with Crystalsev, a Brazilian firm,
to make car fuel out of cane sugar. Not ethanol (though Brazil already
has a thriving market for ethanol-powered cars), but a hydrocarbon
that has the characteristics of diesel fuel. Technically, it is not
ordinary diesel, either: in chemist-speak, it is an isoprenoid rather
than a mixture of alkanes and aromatics. But the driver will not
notice the difference.
The point of the parable is this: biotechnology may have cut its teeth
on medicines, but the big bucks are likely to be in bulk chemicals.
And few chemicals are bulkier than fuels. Where Amyris is leading,
many are following. Some small firms with new and interesting
technologies are trying to go it alone. Others are teaming up with big
energy firms, in much the same way that biotech companies with a
promising drug are often taken under the wing of a large
pharmaceutical company. The big firms themselves are involved, too,
both through in-house laboratories and by giving money to
universities. Biofuels, once seen as a cross between eccentric
greenwash and a politically acceptable way of subsidising farmers, are
now poised to become big business.
The list of things that need to be done to create a proper biofuel
industry is a long one. New crops, tailored to fuel rather than food
production, have to be created. Ways of converting those crops into
feedstock have to be developed. That feedstock has then to be turned
into something that people want to buy, at a price they can afford.
All parts of this chain are currently the subjects of avid research
and development. Some biofuels were already competitive with oil
products even at 2006 oil prices (see table 5). The R&D effort will
bring more of them into line, as will any long-term rise in the price
of crude oil.
As far as the crops themselves are concerned, there are three runners
at the starting gate: grasses, trees and algae. Grasses and trees are
grown on dry land, but need a lot of processing. The idea is to take
the whole biomass of the plant (particularly the cellulose of which a
plant-cell?s walls are made) and turn it into fuel. At the moment,
that fuel is often ethanol. Hence the term "cellulosic ethanol" that
has gained recent currency. Algae, being aquatic, are more fiddly to
grow, but promise a high-quality product, oil, that will not need much
treatment to become biodiesel.
One of the leading proponents of better grasses is Ceres, a firm based
in Thousand Oaks, California. The species it has chosen to
examine—switchgrass, miscanthus, sugarcane and sorghum—are so-called
C4 grasses. These are favourites with the biofuel industry because
they share a particularly efficient form of photosynthesis that
enables them to grow fast. Ceres proposes to make them grow faster
still, using a mixture of "smart" breeding techniques (in which
desirable genes are identified scientifically but assembled into
plants by traditional hybridisation) and straightforward genetic
engineering.
The chosen grasses also thrive in a range of climates. Switchgrass and
miscanthus are temperate. Sugarcane and sorghum are tropical. Ceres
proposes to extend their ranges still further by creating strains that
will tolerate heat or cold or drought or salt, allowing them to be
grown on land that cannot be used for food crops. That will make them
cheaper, as well as reducing the competition between foods and biofuels.
Trees, meanwhile, are the province of firms such as ArborGen, of
Summerville, South Carolina. Like Ceres, ArborGen is working on four
species: eucalyptus, poplar, and the loblolly and radiata pines. It is
applying similar techniques to those used by Ceres to speed up the
growth of these trees and to increase their tolerance of cold.
Although creating raw materials for biofuels is not this company?s
only objective (paper pulp and timber are others), it sees such fuels
as a big market.
Algae, too, are up for modification. One problem with them is
harvesting the oil they produce. That means extracting them from their
ponds, drying them out and breaking open their cells. This process is
so tedious that some companies are considering the idea of burning the
dried algae in power stations instead.
One firm that is not is Synthetic Genomics, the latest venture of
Craig Venter (the man who led the privately funded version of the
Human Genome Project). Dr Venter hopes to overcome the oil-collection
problem by genetic engineering. Synthetic Genomics?s algae have been
fitted with genes that create new secretion pathways through their
outer membranes. These cause the algal cells to expel the oil almost
as soon as they have manufactured it. It then floats to the surface of
the pond, allowing it to be skimmed off like cream and turned into
biodiesel. The algae are also engineered to make more oil than their
wild counterparts.
Harvesting useful fuels from vascular plants, as grasses, trees and
their kind are known collectively, is a trickier business. These
plants are composed mainly of three types of large molecule. Besides
cellulose, there are hemicellulose and lignin. Each is made of chains
of smaller molecules, and all three are often bound together in a
complex called lignocellulose, particularly in wood. There are many
ways these long-chain molecules might be turned into fuel, but all of
these processes are more complex than for algae.
As chart 6 shows, turning sunlight into biofuel involves three steps,
though different methods may miss out some of these steps. Algae can
make the leap from start to finish directly, whereas vascular plants
cannot. One way of dealing with them is to dry them and then heat them
with little or no oxygen present. This is called pyrolysis and, if
done correctly, results in a mixture of carbon monoxide and hydrogen
called "syngas" (short for synthesis gas). With suitable catalysts,
syngas can be turned into fuel.
This is the approach taken by Choren Industries in Freiburg, Germany,
and Range Fuels in Treutlen County, Georgia. In both cases the
feedstock is chippings and other leftovers from forestry and
timbermills. Choren is making hydrocarbon diesel and Range ethanol.
Both factories, therefore, are steps on the road to making fuel from
trees. Syngas can also be turned into ethanol by bacteria of the genus
Clostridium (a group better known for the chemical used in botox
treatment). That is being done by Coskata, a firm based in
Warrenville, Illinois. General Motors (GM) likes this idea so much it
has bought a share of the company.
An alternative to the syngas method is to break the cellulose and
hemicellulose up into their component "monomer" molecules. That is
easier said than done, particularly if lignin is involved, since
lignin is resistant to such conversion. The amount of coal in the
world is proof of its resilience. Coal is composed mainly of lignin
from plants that failed to decompose completely and were fossilised as
a result.
Many firms, however, have developed enzymes that break down biomass in
this way. Iogen, of Ottawa, Canada, was one of the first. Its enzymes
decompose cellulose and hemicellulose into sugar monomers. (The lignin
is burned to generate heat for the process.) Abengoa, a Spanish firm
that is also involved in solar energy, uses this approach as well.
Once you have your sugar, you can ferment it. These days that need not
mean using yeast to make ethanol. A whole range of bugs, some natural,
some engineered, can now be deployed to make a whole range of
products. Amyris?s souped-up micro-organisms (some are bacteria, some
yeasts) turn sugar not into ethanol but into isoprenoids, at a cost
competitive with petroleum-based diesel. LS9, based near San
Francisco, uses a similar method but is turning out alkanes (for
petrol) and fatty acids (for biodiesel). It, too, is starting to scale
up production. Synthetic Genomics is doing something similar, though
the firm is cagey about which fuel is being produced. In each case,
however, what is made is a chemical precisely tailored to its purpose,
rather than the ad hoc mixture that comes out of a refinery. The rival
companies thus argue that their products are actually better than
oil-based ones.
At least one firm, Mascoma, of Cambridge, Massachusetts, employs a
single species of bug, Thermoanaerobacterium saccharolyticum, both to
break down the biomass and to digest the resulting sugar. Mascoma will
use both grass and wood as feedstocks. In May it signed deals with GM
and Marathon Oil.
It is also possible to use purified enzymes to do the conversion from
sugar to fuel, as well as from biomass to sugar, and at least two
firms are working on applying them to the whole process. Codexis,
based in Redwood City, California, has created a range of enzymes by a
method akin to sexual reproduction and natural selection. Last year it
signed a deal with Shell to use this technique to produce biofuels of
various types. And a Danish firm, Danisco, has teamed up with DuPont
to do the same thing with its own proprietary enzymes.
Shell is also involved in a project to turn sugar into hydrocarbons,
this time by straight chemical processing. It is putting up the money.
The technology (the most important part of which is a set of
proprietary non-biological catalysts) is provided by Virent Energy
systems, of Madison, Wisconsin.
Which of these approaches will work best is anybody?s guess. But their
sheer number is proof that the most radical thinking in the field of
renewable energy is going on in biofuels. It is in this area that the
most unexpected breakthroughs are likely to come, says Steven Koonin,
BP?s chief scientist. BP is backing one of the biggest academic
projects intended to look into biofuels, the Energy Biosciences
Institute (EBI), to the tune of $500m, which suggests that the
company?s board agrees with him. The EBI is a partnership of the
University of California, Berkeley, the Lawrence Berkeley National
Laboratory and the University of Illinois.
One of the people involved, Steven Chu, the head of the Lawrence
Berkeley laboratory, is a man with a grand vision. This vision is of a
"glucose economy" that will replace the existing oil economy. Glucose,
the most common monomer sugar, would be turned into fuels and maybe
even the bio-equivalents of petrochemicals—bioplastics, for example—in
local factories and then shipped around the world. That would be a
boon to tropical countries, where photosynthesis is at its most
rampant, though it might not play so well to James Woolsey?s security
fears, since it risks replacing one set of unreliable suppliers with
another.
However, there is plenty of biomass to go around. A study by America?s
Departments of Energy and Agriculture suggests that even with only
small changes to existing practice, 1.3 billion tonnes of plant matter
could be collected from American soil without affecting food
production. If this were converted into ethanol using the best
technology available today, it would add up to the equivalent of 350
billion litres of petrol, or 65% of the country?s current petrol
consumption. And that is before specially bred energy crops and other
technological advances are taken into account. If America wants it,
biofuel autarky looks more achievable than the oil-based sort. And if
it does not, then the world?s hitherto impoverished tropics may find
themselves in the middle of an unexpected and welcome industrial
revolution.
posted to ClimateConcern
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